Common Drainage Problems

Croft Drainage specialise in drainage problems across Nottinghamshire and Lincolnshire.

Our approachable and local team are always on hand to help with any drainage problem.

If you are experiencing septic tank problems, cesspit problems or drainage field issues, and are based in Lincolnshire or Nottinghamshire, the experts at Croft Drainage should be your first call.

This really helpful guide from British Water might help with understanding the code of practice for wastewater treatment systems.


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Drainage problems to be on the look out for…

The first sign you may have a problem can range from a flooded garden, or other land drainage problems to strange smells and difficulty flushing the toilet.

These can be the symptoms of a more serious problem, it is best to get any issues checked by a professional as soon as possible. A small call-out fee is a far better measure than the cost of structural damage or a new drainage system installation. If you live within a 20-mile radius of Gainsborough, our initial site visit is free!

Other drainage issues to keep an eye out for are:

  • Slowly draining sinks, toilets and baths, often accompanied by gurgling sounds
  • Covers on the drains or chambers lifting
  • Unusual sewage smells in the vicinity of the plant or tank
  • Sewage backing up at the inlet to the sewage treatment plant or aerobic septic tank
  • Sewage smells in the vicinity of the plant or tank (different to the ‘normal’ smells around the plant)
  • Grey and cloudy final effluent.

Mr B, Stallingborough

From the initial site visit to completion of the installation we were very satisfied with the service we received. Ben communicated very well during the installation regarding the organising of other contractors and progress of the installation itself. Other family members and neighbours commented on how organised and clean the team worked considering our property sits on a communal driveway. We felt we received a very thorough service and would happily recommend Croft Drainage Solutions to friends and family.

Typical septic tank problems

Most common septic tank drainage problems and failures are due to the drainage field and not to the septic tank itself. There is one thing certain about a septic tank drainage field, it will at some stage fail.

  • Blockages causing flooding within the system, including roots blocking pipes
  • Structural damage leading to leakage. Due to damage by roots from nearby trees, large shrubs, ground subsidence or from vehicles
  • Excess water volume entering the tank. This overloads the system and can lead to flooding and land pollution. Rainwater from roofs, paved, tarmacked or concreted areas should not pass through a septic tank system. These flows should be directed elsewhere
  • Lack of maintenance can cause a build-up of sludge within the septic tank. Which can then cause the drainage field to fail as solids pass through the system without settling out in the septic tank
  • Incorrectly sized septic tanks not treating the waste correctly.  This leads to sewage (including the solids) being short circuited into the drainage field where they cause blockages
  • Collapsed baffles, which help prevent the solid waste leaving the main tank.  Which can result in floating waste moving into the drainage field pipework
  • Damaged Dip Pipes, commonly caused when tank is being emptied.  Which can leads to drainage field failures
  • Excessive volumes of chemicals or detergents added to the septic tank. These affect bacteria and enzymes in a tank.
More about septic tanks

Drainage field problems

If you have established your problem to be arising from your drainage field, not your septic tank, these are the common issues:

  • The water table in the surrounding soils becomes too high. This means the effluent will go straight into the water table without being correctly treated first
  • If the septic tank fails, raw effluent can start to flow into the drainage field which causes it to fail, ultimately resulting in failure of the whole system. Damaged dip pipes often cause drainage field problems
  • If the drainage field is in an area of clay based soil, the water will not be able to pass out of the system and into the soil. This usually indicates a percolation test did not take place
  • An increased volume of waste entering the drainage field and septic tank.  For example, rainwater runoff connected to the system. This can have a detrimental effect on the whole system, as they are only designed to cope with a specific volume per day.  Overloading can result in waste clogging the drainage field
  • Surrounding trees and shrubs can cause septic tank drainage field problems. Root ingress damages the system’s structure and cause pipe blockages
  • Drainage field structure damaged by vehicles or heavy machinery travelling over the system. The surrounding soil or pipes can get compacted which will reduce its permeability
  • A drainage field needs to be at a depth where aerobic bacteria are present.  Any deeper than this, and the bacteria found tends to be anaerobic.  These can produce a black slimy substance that can block the drainage field and affect the permeability of the surrounding soil. Croft Drainage can supply aerobic septic systems in Lincolnshire, to suit your requirements.
More about drainage fields

Common Cesspit problems

The following are common problems associated with cesspits:

  • Flooding due to tank damage caused by tree roots, ground movement or vehicles
  • Roof Collapses (Cesspits tend to cover large areas)
  • Structural problems. As tanks age they start to deteriorate (especially older brick built tanks). This can result in leaks and pollution of the surrounding areas
  • Lack of maintenance. Tanks not emptied often enough can lead to flooding around the tank and problems in the connected drains
  • Bad Practise – in some cases the tanks are ‘modified’ to allow them to drain out into a watercourse. This leads to pollution and associated issues such as smells
More about cesspits

Potential sewage treatment plant problems

There are many problems that may affect your sewage treatment plant, including:

  • Overloading causing effluent failure. Can be due to change of use (extensions built) or surface water entering the system
  • Failed blower or pump
  • Blocked pumps
  • High levels of fats, oils and greases overloading the plant
  • Insufficient retention time in the STP due to hydraulic overloading
  • Chemical overloading and inhibiting bacterial action in the STP
  • Poorly installed sewage treatment plant lifting out of the ground
  • Splits in the walls of the treatment plant
  • Damage caused by tree roots, ground movement or vehicles leading to the sewage treatment plant becoming displaced or damaged
More about sewage treatment plants